Air/Fuel Mixture: Testing and Inspection

INSPECTION

HINT: This check is used only to determine whether or not the idle CO/HC complies with regulations.

1. INITIAL CONDITIONS
- Engine at normal operating temperature
- Air cleaner installed
- All pipes and hoses of air induction system connected
- All accessories switched OFF
- All vacuum lines properly connected

HINT: All vacuum hoses for EGR systems, etc. should be properly connected.

- MFI system wiring connectors fully plugged
- Ignition timing check correctly
- Transmission in neutral position
- Tachometer and CO/HO meter calibrated by hand
2. START ENGINE
3. RACE ENGINE AT 2,500 RPM FOR APPROX. 180 SECONDS





4. INSERT CO/HC METER TESTING PROBE AT LEAST 40 cm (1.3 ft) INTO TAILPIPE DURING IDLING
5. IMMEDIATELY CHECK CO/HC CONCENTRATION AT IDLE AND/OR 2,500 RPM

HINT: When doing the 2 mode (idle and 2,500 rpm) test, these measurement order prescribed by the applicable local regulations.





Troubleshooting
If the CO/HO concentration does not comply with regulations, troubleshoot according to the table above.
- Check heated oxygen sensor operation.
- Check and correct the cause if necessary